The invention relates to a valve, especially a plate valve, for example, for diaphragm pumps, with a valve plate, a valve seat, and a valve chamber bounded by a valve housing, with the valve plate being held at the edges.
Valves of this type are already known. In combination with the valve seat, the valve plate used in plate valves has the task of providing a passive valve function triggered by the flow and pressure difference, as required in diaphragm pumps or non-return valves.
In the already known valves, in addition to its actual function, namely forming a seal with the valve seat, the valve plate also fulfills additional functions, such as, for example, sealing the valve housing from the outside. For this purpose, there are regions, which fulfill these functions, on the valve plate. In particular, in the installation of such valve plates combining such a sealing function, an undefined installation position or stress in the actual valve plate can result during installation due to squeezing in the seal regions outwards primarily due to the lack of compressibility of rubber, which is often used. Solutions to reduce this stress by means of stress-reducing grooves are known, but are not sufficient, especially for small pumps or micro-pumps and the tight tolerances necessary with these devices. In this range, very small dimensional deviations can produce disadvantageous effects on the correct valve function, that is, on the correct position of the valve plate relative to the valve seat and the sealing capability of both elements.